SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c6052b3e4fa6e74a6d96fafb37cba82f5da6bb9f8afb4cae487a8345eaef851b' 
  AND token = 'clVWmUVSJXVSgYE2IC4PXcVCyZLw+yK23jDaZrDMWoU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}